We do begin with that developing news that terrorists' takeover of that natural gas facility in algeria has finally come to an deadly end tonight. The algerian military moving in, leaving many dead. Including at least 23 hostages. One american among them. Still other americans unaccounted for. For the first time it began, we're getting a first look held inside the plant. Hostages kneeling in the sand there, hands in the air. This new video reportedly shot by workers as they escaped through the desert. In a moment the stories of the survival. But we begin with abc's chief investigative correspondent brian ross tonight. Reporter: The algerian's army final assault today recaptured the bp-run facility but left many of the hostages dead. Over the four-day siege in the middle of the sahara desert, the final hostage death toll was put at by algerian officials at 53. For their family and friends has been and continues to be a distressing and horrific time. Reporter: At least two americans remain unaccounted for and one american has confirmed as killed. 58-year-old fred buttacio of katy, texas, a suburb of houston. We believe that there are five british nationals and one uk resident who are either deceased or unaccounted for. Reporter: The good news was, most of the western workers were freed or escaped. Algerian tv aired what it said was home video taken by on hostage as he escaped across the desert. Among those who also got out was mark cobb of corpus christi, texas, described as the vp/senior manager at the facility. Their bodies displayed today on tv. Officials said they were heavily armed with automatic weapons and explosives-packed belts. As algerian tanks and special forces surrounded the plant, officials said they had no choice but to go in with guns blazing. Even after other countries asked them to hold off out of concern for the safety of hostages. We don't negotiate. We don't mess around. The official algerian news agency said they began to execute the remaining hostages as the algerian army moved in. Now it will shift to the master mind of this attack, mokhtar, david, he's made himself one of the most wanted

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